I went on vacation for 15 days and my car stayed.

I went on vacation for 15 days and my car stayed idle during this time. I had taken out battery wires to ensure that battery won't be discharged.

When I came back, I saw a lot of Carbon on the terminals of battery. I put hot water on it to clean the carbon and then started the car. It took the ignition with its battery but the engine started to take jerks.

I went for a drive and I felt that when I am giving the accelerator, it is working fine but once I put the breaks (car is automatic), it feels as if engine will shut down.

Next day I tried to start the car but the problem is even more now and as soon as I put the car in gear, the engine shuts down. RPMs are staying at around 0.7 or 0.8 which is how they were in the past but the engine is shaking as if not getting full current.

Kindly advise me so that I can bring the proper mechanic.